(1) Field of the Invention
This invention relates to a fragrant article using gradually decomposing perfume.
(2) Description of the Prior Art
There have hitherto been such impregnation type fragrant articles as formed by adding a perfume to a sublimable substance such as para-dichlorobenzene, etc. or to crystalline cellulose, etc. as an excipient. However, all of these fragrant articles have only a small amount of perfume added thereto. Under the circumstances, they have drawbacks such as a short duration of volatilizing the aroma, and weak aroma.
There have been recently available improved plastic fragrant articles formed by compounding a perfume in a plastic such as vinyl chloride, etc. There is however required a high temperature for mixing plastics with perfume, because they are, in general, poorly compatible with each other. This makes it unfavorable to use a volatile perfume, resulting in that choice of the variety of perfumes is naturally limited. There is also a drawback in that although the aroma is strong enough in the initial stage of use, the intensity of the aroma notably decreases in a few days.
There have also been marketed several types of fragrant articles wherein a perfume is added to impart aromaticity to a pregnant, such as filter paper, chipboard used as building material, zeolite, silica gel or the like. The perfume for this purpose is rarely used in a singular form, and there are used several blend perfumes arranged by mixing various kinds of single perfumes, which have strong aroma. Since, in this case, the volatilization rates of the respective perfume components differ from one another, the composition of the perfume changes with the lapse of time, resulting in change of the fragrance tone. In order to resolve this problem, there are often added, as a retainer, balsam, benzoin, musk, glycols, or phthalates, as they have low volatility, strong affinity and high retainability. However, these types of retainers not only supress the volatilization rates of these components having high volatilization rates, but also supress the volatilization rates of those components of low volatilization rates. As a result, the aroma tends to be weak.